I disagree with most of the points. Mostly, I do not agree that it should have been a 9mm.

Both the LCP and LC9 shoot like crap, they are both too small and/or lightweight for their respective calibers (imo). Sure, they make great belly guns, perhaps great pocket guns, and they can shoot decently when taking your time; but they provide scatter patterned groups when shot rapid fire at 7 to 10 yards.

I wear a large to x-large glove (I don't have small hands) and the G42 feels better in my hand than the Shield does. I'm definitely not 'recoil sensitive'. But, the G42 and Shield aren't really direct competitors, imo. One is smaller/lighter, with a smaller round - the other larger/heavier with a larger caliber. They both do their intended job well.

Personally, I think the Shield is the next logical step in size/caliber progression. The G42 is perfect in size/weight for it's caliber (its about the same size as a Colt Govt. Model 380 , for example) and the Shield adds just enough size and weight to warrant the 9mm cartridge - anything smaller and it'd just be another shitty shooting LCP or LC9. I suspect that if/when Glock does a single stack 9mm, it will just be a slimmed down G26, perhaps with a very slight reduction in barrel length. I'd assume for practical purposes, it would be more or less the size and weight of a Shield. When I first shot the G42, I did rapid fire drills back to back against the Kahr CM9. I'll let you guess which one I left with.

I carried an LCP .380 for years, a sufficiently accurate gun in capable hands (2-3" rapid fire groups at 7 yards, 8" plates at 50 yards), but couldn't justify the defensive compromise any longer once the Shield came out in 40S&W.

I carried an LCP .380 for years, a sufficiently accurate gun in capable hands (2-3" rapid fire groups at 7 yards, 8" plates at 50 yards), but couldn't justify the defensive compromise any longer once the Shield came out in 40S&W.

See, I'm on the other end. I couldn't justify the accuracy compromise. I maybe didn't have enough time behind the LCP (lets be honest, its not fun to shoot), but I could never come even close to 3" groups for a true rapid fire at 7-10 yards. I'm fine with .380 for daily 'out and about' defense.

A typical .380 XTP round will penetrate bare gel and heavy denim+gel to around ~13-14.5", with expansion just under a 1/2" inch while a typical 9mm (Say the Federal HST) will penetrate 15-17" and expand just over a 1/2"; out of a ~3" barrel.

9mm is better, no question. But, most people don't give enough credit to the .380, especially when they are using rounds like the Hornady Critical Defense (or other immensely popular rounds) out of a 2.8" barrel as it's benchmark. However, I agree that 9mm gives one more of a warm and fuzzy feeling.

The Glock 42 should really be put up against a Bodyguard, LCP or P3at, not a Shield.

I agree with you, the aforementioned would be a more pertinent comparison, however thanks to the OP as I still found this comparison to be quite interesting. I've recently considered both guns for soon purchase and the pics were quite relevant to me. Thanks OP!!